Now available with an S9 protocol to detect genotoxic metabolites, GreenScreen HC from Gentronix is a human cell-based genotoxicity screening assay used in drug discovery programmes during lead compound optimisation and candidate selection.

Potential pharmaceutical compounds which only present a genotoxicity hazard after metabolism, usually by the liver, are known as pro-genotoxins. The utility of GreenScreen HC has now been extended to detect pro-genotoxins as well as all common mechanistic classes of genotoxin including mutagens, clastogens, aneugens, as well as both topoisomerase and polymerase inhibitors.

Using a standardized 96-well microplate format, the test compound and patented Green Fluorescent Protein (GFP) reporter cells are combined with 1% S9 for a 3 hour exposure period. After exposure, cells are washed to remove the S9 and test compound and then allowed a further 45 hour recovery incubation. Cell viability and GFP fluorescence data are assessed using flow cytometry and simple software generates quantitative results and a graphical output.

Minimal investment in early genotoxicity screening delivers major time savings, avoids unnecessary animal testing and prevents costly late stage failures of lead drug compounds through early detection of genotoxic potential. Combining exceptional levels of specificity and sensitivity, GreenScreen HC also correctly identifies non-carcinogenic compounds known to give misleading positive results in other in vitro genotoxicity assays.